Search results for: nature and elements as medicine
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8974

Search results for: nature and elements as medicine

784 The Use of Punctuation by Primary School Students Writing Texts Collaboratively: A Franco-Brazilian Comparative Study

Authors: Cristina Felipeto, Catherine Bore, Eduardo Calil

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This work aims to analyze and compare the punctuation marks (PM) in school texts of Brazilian and French students and the comments on these PM made spontaneously by the students during the ongoing text. Assuming textual genetics as an investigative field within a dialogical and enunciative approach, we defined a common methodological design in two 1st year classrooms (7 years old) of the primary school, one classroom in Brazil (Maceio) and the other one in France (Paris). Through a multimodal capture system of writing processes in real time and space (Ramos System), we recorded the collaborative writing proposal in dyads in each of the classrooms. This system preserves the classroom’s ecological characteristics and provides a video recording synchronized with dialogues, gestures and facial expressions of the students, the stroke of the pen’s ink on the sheet of paper and the movement of the teacher and students in the classroom. The multimodal register of the writing process allowed access to the text in progress and the comments made by the students on what was being written. In each proposed text production, teachers organized their students in dyads and requested that they should talk, combine and write a fictional narrative. We selected a Dyad of Brazilian students (BD) and another Dyad of French students (FD) and we have filmed 6 proposals for each of the dyads. The proposals were collected during the 2nd Term of 2013 (Brazil) and 2014 (France). In 6 texts written by the BD there were identified 39 PMs and 825 written words (on average, a PM every 23 words): Of these 39 PMs, 27 were highlighted orally and commented by either student. In the texts written by the FD there were identified 48 PMs and 258 written words (on average, 1 PM every 5 words): Of these 48 PM, 39 were commented by the French students. Unlike what the studies on punctuation acquisition point out, the PM that occurred the most were hyphens (BD) and commas (FD). Despite the significant difference between the types and quantities of PM in the written texts, the recognition of the need for writing PM in the text in progress and the comments have some common characteristics: i) the writing of the PM was not anticipated in relation to the text in progress, then they were added after the end of a sentence or after the finished text itself; ii) the need to add punctuation marks in the text came after one of the students had ‘remembered’ that a particular sign was needed; iii) most of the PM inscribed were not related to their linguistic functions, but the graphic-visual feature of the text; iv) the comments justify or explain the PM, indicating metalinguistic reflections made by the students. Our results indicate how the comments of the BD and FD express the dialogic and subjective nature of knowledge acquisition. Our study suggests that the initial learning of PM depends more on its graphic features and interactional conditions than on its linguistic functions.

Keywords: collaborative writing, erasure, graphic marks, learning, metalinguistic awareness, textual genesis

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783 Dietary Factors Contributing to Osteoporosis among Postmenopausal Women in Riyadh Armed Forces Hospital

Authors: Rabab Makki

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Bone mineral density and bone metabolism are affected by various factors such as genetic, endocrine, mechanical and nutritional. Our understanding of nutritional influences on bone health is limited because most studies have focused on calcium. This study investigated the dietary factors which are likely t contribute to Osteoporosis in Saudi post-menopausal women, and correlated it with BMD. This is a case controlled study involved 36 postmenopausal Saudi females selected from the Orthopedics and osteoporosis outpatient clinics, and 25 postmenopausal Saudi females as controls from the primary clinic of Military Hospital in Riyadh. The women were diagnosed as osteoporotic based on the BMD measurement at any site (left femur neck, right femur neck, left total hip or right total hip or spine). Both the controls and the Osteoporotics were over 50 years of age and BMI between 31-34 kg/m2 had 2nd degree obesity, and were not free from other problems such as diabetes, hypertension, etc. Subjects (osteoporotics and controls) were interviewed to called data on demographic characterstics, medical history, dietary intake anthropometry (height and weight) bone mineral density. Blood samples were collected from subjects (Osteoporotics and controls). Analysis of serum calcium, vitamin D, phosphate were done at the main laboratory at Military Hospital Riyadh, by the laboratory technician while BMD was determined at the department of Nuclear Medicine by an expert technician and results were interpreted by radiologist.Data on frequency of consumption of animal food (meat, eggs, poultry and fish) and diary foods (milk, yogurt, cheese) of osteoporotic was less than control. In spite of the low intake there was no association with BMD.In general, the vegetables and fruits were consumed less by the osteoporotics than control. The only fruit which had shown a significant positive correlation is banana with right and left hip BMD total probably due to high potassium and minerals content which likely to prevent bone resorption. Mataziz vegetables combination of wheat showed a significant positive correlation with the same site (total right and left hip). Both osteoporotics abd controls were consuming table sugar. (But the sweet intake showed a significant negative correlation with left neck femur BMD, suggesting sucrose increase urinary calcium loss. Both osteoporotic and controls were consuming Arabic coffee. A negative significant correlation between intake of Arabic coffee and BMD of right neck femur of osteoporosis patient was observed. It could be suggested that increased intake of fruits and vegetables, might promote bone density while high intake of coffee and sugars might affect bone density, no significant correlation was observed between BMD at any site and diary product. We can say the major risk factors are inadequate nutrition. Further studies are needed among Saudi population to confirm these results.

Keywords: osteoporosi, Saudia Arabia, Riyadh Armed Forces, postmenopausal women

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782 A Doctrinal Research and Review of Hashtag Trademarks

Authors: Hetvi Trivedi

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Technological escalation cannot be negated. The same is true for the benefits of technology. However, such escalation has interfered with the traditional theories of protection under Intellectual Property Rights. Out of the many trends that have disrupted the old-school understanding of Intellectual Property Rights, one is hashtags. What began modestly in the year 2007 has now earned a remarkable status, and coupled with the unprecedented rise in social media the hashtag culture has witnessed a monstrous growth. A tiny symbol on the keypad of phones or computers is now a major trend which also serves companies as a critical investment measure in establishing their brand in the market. Due to this a section of the Intellectual Property Rights- Trademarks is undergoing a humungous transformation with hashtags like #icebucket, #tbt or #smilewithacoke, getting trademark protection. So, as the traditional theories of IP take on the modern trends, it is necessary to understand the change and challenge at a theoretical and proportional level and where need be, question the change. Traditionally, Intellectual Property Rights serves the societal need for intellectual productions that ensure its holistic development as well as cultural, economic, social and technological progress. In a two-pronged effort at ensuring continuity of creativity, IPRs recognize the investment of individual efforts that go into creation by way of offering protection. Commonly placed under two major theories- Utilitarian and Natural, IPRs aim to accord protection and recognition to an individual’s creation or invention which serve as an incentive for further creations or inventions, thus fully protecting the creative, inventive or commercial labour invested in the same. In return, the creator by lending the public the access to the creation reaps various benefits. This way Intellectual Property Rights form a ‘social contract’ between the author and society. IPRs are similarly attached to a social function, whereby individual rights must be weighed against competing rights and to the farthest limit possible, both sets of rights must be treated in a balanced manner. To put it differently, both the society and the creator must be put on an equal footing with neither party’s rights subservient to the other. A close look through doctrinal research, at the recent trend of trademark protection, makes the social function of IPRs seem to be moving far from the basic philosophy. Thus, where technology interferes with the philosophies of law, it is important to check and allow such growth only in moderation, for none is superior than the other. The human expansionist nature may need everything under the sky that can be tweaked slightly to be counted and protected as Intellectual Property- like a common parlance word transformed into a hashtag, however IP in order to survive on its philosophies needs to strike a balance. A unanimous global decision on the judicious use of IPR recognition and protection is the need of the hour.

Keywords: hashtag trademarks, intellectual property, social function, technology

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781 Application of the State of the Art of Hydraulic Models to Manage Coastal Problems, Case Study: The Egyptian Mediterranean Coast Model

Authors: Alsayed Ibrahim Diwedar, Ahmed ElKut, Mohamed Yossef

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Coastal problems are stressing the coastal environment due to its complexity. The dynamic interaction between the sea and the land results in serious problems that threaten coastal areas worldwide, in addition to human interventions and activities. This makes the coastal environment highly vulnerable to natural processes like flooding, erosion, and the impact of human activities as pollution. Protecting and preserving this vulnerable coastal zone with its valuable ecosystems calls for addressing the coastal problems. This, in the end, will support the sustainability of the coastal communities and maintain the current and future generations. Consequently applying suitable management strategies and sustainable development that consider the unique characteristics of the coastal system is a must. The coastal management philosophy aims to solve the conflicts of interest between human development activities and this dynamic nature. Modeling emerges as a successful tool that provides support to decision-makers, engineers, and researchers for better management practices. Modeling tools proved that they are accurate and reliable in prediction. With its capability to integrate data from various sources such as bathymetric surveys, satellite images, and meteorological data, it offers the possibility for engineers and scientists to understand this complex dynamic system and get in-depth into the interaction between both the natural and human-induced factors. Enabling decision makers to make informed choices and develop effective strategies for sustainable development and risk mitigation. The application of modeling tools supports the evaluation of various scenarios by affording the possibility to simulate and forecast different coastal processes from the hydrodynamic and wave actions and the resulting flooding and erosion. The state-of-the-art application of modeling tools in coastal management allows for better understanding and predicting coastal processes, optimizing infrastructure planning and design, supporting ecosystem-based approaches, assessing climate change impacts, managing hazards, and finally facilitating stakeholder engagement. This paper emphasizes the role of hydraulic models in enhancing the management of coastal problems by discussing the diverse applications of modeling in coastal management. It highlights the modelling role in understanding complex coastal processes, and predicting outcomes. The importance of informing decision-makers with modeling results which gives technical and scientific support to achieve sustainable coastal development and protection.

Keywords: coastal problems, coastal management, hydraulic model, numerical model, physical model

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780 Chemical Study and Cytotoxic Activity of Extracts from Erythroxylum Genus against HeLa Cells

Authors: Richele P. Severino, Maria M. F. Alchaar, Lorena R. F. De Sousa, Patrik S. Vital, Ana G. Silva, Rosy I. M. A. Ribeiro

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Recognized as a global biodiversity hotspot, the Cerrado (Brazil) presents an extreme abundance of endemic species and it is considered to be one of the biologically richest tropical savanna regions in the world. Erythroxylum genus is found in Cerrado and chemically is characterized by the presence of tropane alkaloids, among them cocaine, a natural alkaloid produced by Erythroxylum coca Lam., which was used as a local anesthetic in small surgeries. However, cocaine gained notoriety due to its psychoactive activity in the Central Nervous System (CNS), becoming one of the major problems of public health today. Some species of Erythroxylum are referred to in the literature as having pharmacological potential, which provide alkaloids, terpenoids, and flavonoids. E. vacciniifolium Mart., commonly known as 'catuaba', is used as a central nervous system stimulant and has aphrodisiac properties and E. pelleterianum A. St.-Hil. in the treatment of stomach pains. Already E. myrsinites Mart. and E. suberosum A. St.-Hil. are used in the tannery industry. Species of Erythroxylum are also used in folk medicine for various diseases, against diabetes, antiviral, fungicidal, cytotoxicity, among others. The Cerrado is recognized as the richer savannah in the world in biodiversity but little explored from the chemical view. In our on-going study of the chemistry of Erythroxylum genus, we have investigated four specimens collected in central Cerrado of Brazil: E. campestre (EC), E. deciduum (ED), E. suberosum (ES) and E. tortuosum (ET). The cytotoxic activity of extracts was evaluated using HeLa cells, in vitro assays. The chemical investigation was performed preparing the extracts using n-hexane (H), dichloromethane (D), ethyl acetate (E) and methanol (M). The cells were treated with increasing concentrations of extracts (50, 75 and 100 μg/mL) diluted in DMSO (1%) and DMEM (0.5% FBS and 1% P/S). The IC₅₀ values were determined measured spectrophotometrically at 570 nm, after incubation of HeLa cell line for 48 hours using the MTT (SIGMA M5655), and calculated by nonlinear regression analysis using GraphPad Prism software. All the assays were done in triplicate and repeated at least two times. The cytotoxic assays showed some promising results with IC₅₀ values less than 100 μg/mL (ETD = 38.5 μg/mL; ETM = 92.3 μg/mL; ESM = 67.8 μg/mL; ECD = 24.0 μg/mL; ECM = 32.9; EDA = 44.2 μg/mL). The chemical profile study of ethyl acetate (E) and methanolic (M) extracts of E. tortuosum leaves was performed by LC-MS, and the structures of the compounds were determined by analysis of ¹H, HSQC and HMBC spectra, and confirmed by comparison with the literature data. The investigation led to six substances: α-amyrin, β-amyrin, campesterol, stigmastan-3,5-diene, β-sitosterol and 7,4’-di-O-methylquercetin-3-O-β-rutinoside, with flavonoid the major compound of extracts. By alkaline extraction of the methanolic extract, it was possible to identify three alkaloids: tropacocaine, cocaine and 6-methoxy-8-methyl-8-azabicyclo[3.2.1]octan-3-ol. The results obtained are important for the chemical knowledge of the Cerrado biodiversity and brought a contribution to the chemistry of Erythroxylum genus.

Keywords: cytotoxicity, Erythroxylum, chemical profile, secondary metabolites

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779 Evaluating the Benefits of Intelligent Acoustic Technology in Classrooms: A Case Study

Authors: Megan Burfoot, Ali GhaffarianHoseini, Nicola Naismith, Amirhosein GhaffarianHoseini

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Intelligent Acoustic Technology (IAT) is a novel architectural device used in buildings to automatically vary the acoustic conditions of space. IAT is realized by integrating two components: Variable Acoustic Technology (VAT) and an intelligent system. The VAT passively alters the RT by changing the total sound absorption in a room. In doing so, the Reverberation Time (RT) is changed and thus, the sound strength and clarity are altered. The intelligent system detects sound waves in real-time to identify the aural situation, and the RT is adjusted accordingly based on pre-programmed algorithms. IAT - the synthesis of these two components - can dramatically improve acoustic comfort, as the acoustic condition is automatically optimized for any detected aural situation. This paper presents an evaluation of the improvements of acoustic comfort in an existing tertiary classroom located at Auckland University of Technology in New Zealand. This is a pilot case study, the first of its’ kind attempting to quantify the benefits of IAT. Naturally, the potential acoustic improvements from IAT can be actualized by only installing the VAT component of IAT and by manually adjusting it rather than utilizing an intelligent system. Such a simplified methodology is adopted for this case study to understand the potential significance of IAT without adopting a time and cost-intensive strategy. For this study, the VAT is built by overlaying reflective, rotating louvers over sound absorption panels. RT's are measured according to international standards before and after installing VAT in the classroom. The louvers are manually rotated in increments by the experimenter and further RT measurements are recorded. The results are compared with recommended guidelines and reference values from national standards for spaces intended for speech and communication. The results obtained from the measurements are used to quantify the potential improvements in classroom acoustic comfort, where IAT to be used. This evaluation reveals the current existence of poor acoustic conditions in the classroom caused by high RT's. The poor acoustics are also largely attributed to the classrooms’ inability to vary acoustic parameters for changing aural situations. The classroom experiences one static acoustic state, neglecting to recognize the nature of classrooms as flexible, dynamic spaces. Evidently, when using VAT the classroom is prescribed with a wide range of RTs it can achieve. Namely, acoustic requirements for varying teaching approaches are satisfied, and acoustic comfort is improved. By quantifying the benefits of using VAT, it can confidently suggest these same benefits are achieved with IAT. Nevertheless, it is encouraged that future studies continue this line of research toward the eventual development of IAT and its’ acceptance into mainstream architecture.

Keywords: acoustic comfort, classroom acoustics, intelligent acoustics, variable acoustics

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778 Grain Size Statistics and Depositional Pattern of the Ecca Group Sandstones, Karoo Supergroup in the Eastern Cape Province, South Africa

Authors: Christopher Baiyegunhi, Kuiwu Liu, Oswald Gwavava

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Grain size analysis is a vital sedimentological tool used to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. In this study, detailed grain-size analysis was carried out on thirty-five sandstone samples from the Ecca Group in the Eastern Cape Province of South Africa. Grain-size statistical parameters, bivariate analysis, linear discriminate functions, Passega diagrams and log-probability curves were used to reveal the depositional processes, sedimentation mechanisms, hydrodynamic energy conditions and to discriminate different depositional environments. The grain-size parameters show that most of the sandstones are very fine to fine grained, moderately well sorted, mostly near-symmetrical and mesokurtic in nature. The abundance of very fine to fine grained sandstones indicates the dominance of low energy environment. The bivariate plots that the samples are mostly grouped, except for the Prince Albert samples that show scattered trend, which is due to the either mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function (LDF) analysis is dominantly indicative of turbidity current deposits under shallow marine environments for samples from the Prince Albert, Collingham and Ripon Formations, while those samples from the Fort Brown Formation are fluvial (deltaic) deposits. The graphic mean value shows the dominance of fine sand-size particles, which point to relatively low energy conditions of deposition. In addition, the LDF results point to low energy conditions during the deposition of the Prince Albert, Collingham and part of the Ripon Formation (Pluto Vale and Wonderfontein Shale Members), whereas the Trumpeters Member of the Ripon Formation and the overlying Fort Brown Formation accumulated under high energy conditions. The CM pattern shows a clustered distribution of sediments in the PQ and QR segments, indicating that the sediments were deposited mostly by suspension and rolling/saltation, and graded suspension. Furthermore, the plots also show that the sediments are mainly deposited by turbidity currents. Visher diagrams show the variability of hydraulic depositional conditions for the Permian Ecca Group sandstones. Saltation is the major process of transportation, although suspension and traction also played some role during deposition of the sediments. The sediments were mainly in saltation and suspension before being deposited.

Keywords: grain size analysis, hydrodynamic condition, depositional environment, Ecca Group, South Africa

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777 Use of Proton Pump Inhibitors Medications during the First Years of Life and Late Complications

Authors: Kamelia Hamza

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Background: Proton pump inhibitors (PPIs) are the most prescribed drug classes for pediatric gastroesophageal reflux disease (GERD).Many patients are treated with these drugs for atypical manifestations attributed to gastroesophageal reflux (GER), even in the absence of proved causal relationship. There is an impression of increase use of PPI's treatment for reflux in "clalit health services," the largest health organization in Israel. In the recent years, the medicine is given without restriction, it's not limited to pediatric gastroenterologists only, but pediatricians and family doctors. The objective of this study is to evaluate the hypothesis that exposure to PPIs during the first year of life is associated with an increased risk of developing late adverse diseases: pneumonia, asthma, AGE, IBD, celiac disease, allergic disorders, obesity, attention deficit hyperactivity disorders (ADHD), autism spectrum disorders (ASD). Methods: The study is a retrospective case-control cohort study based on a computerized database of Clalit Health Services (CHS). It includes 9844 children born between 2002-2018 and reported to complain of at least one of the symptoms (reflux/ spitting up, irritability, feeding difficulties, colics). The study population included the study group (n=4922) of children exposed to PPIs at any time prior to the first year of life and a control group (n=4922) child not exposed to PPIs who were matched to each case of the study group on age, race, socioeconomic status, and year of birth. The prevalence of late complications/diseases in the study group was compared with the prevalence of late complications/diseases diagnosis between 2002-2020 in the control group. Odds ratios and 95% confidence intervals were calculated by using logistic regression models. Results: We found that compared to the control group, children exposed to PPIs in the first year of life had an increased risk of developing several late complications/ disorders: pneumonia, asthma, various allergies (urticaria, allergic rhinitis, or allergic conjunctivitis) OR, inhalant allergies, and food allergies. In addition, they showed an increased risk of being diagnosed with ADHD or ASD, but children exposed to PPIs in the first year of life had decrease the risk of obesity by 17% (OR 0.825, 95%CI 0.697-0.976). Conclusions: We found significant associations between the use of PPIs during the first year of life and subsequent development of late complications/diseases such as respiratory diseases, allergy diseases, ADHD, and ASD. More studies are needed to prove causality and determine the mechanism behind the effect of PPIs and the development of late complications.

Keywords: acid suppressing medications, proton pump inhibitors, histamine 2 blocker, late complications, gastroesophageal reflux, gastroesophageal reflux disease, acute gastroenteritis, community acquired pneumonia, asthma, allergic diseases, obesity, inflammatory bowel diseases, ulcerative colitis, crohn disease, attention deficit hyperactivity disorders, autism spectrum disorders

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776 Curcumin Nanomedicine: A Breakthrough Approach for Enhanced Lung Cancer Therapy

Authors: Shiva Shakori Poshteh

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Lung cancer is a highly prevalent and devastating disease, representing a significant global health concern with profound implications for healthcare systems and society. Its high incidence, mortality rates, and late-stage diagnosis contribute to its formidable nature. To address these challenges, nanoparticle-based drug delivery has emerged as a promising therapeutic strategy. Curcumin (CUR), a natural compound derived from turmeric, has garnered attention as a potential nanomedicine for lung cancer treatment. Nanoparticle formulations of CUR offer several advantages, including improved drug delivery efficiency, enhanced stability, controlled release kinetics, and targeted delivery to lung cancer cells. CUR exhibits a diverse array of effects on cancer cells. It induces apoptosis by upregulating pro-apoptotic proteins, such as Bax and Bak, and downregulating anti-apoptotic proteins, such as Bcl-2. Additionally, CUR inhibits cell proliferation by modulating key signaling pathways involved in cancer progression. It suppresses the PI3K/Akt pathway, crucial for cell survival and growth, and attenuates the mTOR pathway, which regulates protein synthesis and cell proliferation. CUR also interferes with the MAPK pathway, which controls cell proliferation and survival, and modulates the Wnt/β-catenin pathway, which plays a role in cell proliferation and tumor development. Moreover, CUR exhibits potent antioxidant activity, reducing oxidative stress and protecting cells from DNA damage. Utilizing CUR as a standalone treatment is limited by poor bioavailability, lack of targeting, and degradation susceptibility. Nanoparticle-based delivery systems can overcome these challenges. They enhance CUR’s bioavailability, protect it from degradation, and improve absorption. Further, Nanoparticles enable targeted delivery to lung cancer cells through surface modifications or ligand-based targeting, ensuring sustained release of CUR to prolong therapeutic effects, reduce administration frequency, and facilitate penetration through the tumor microenvironment, thereby enhancing CUR’s access to cancer cells. Thus, nanoparticle-based CUR delivery systems promise to improve lung cancer treatment outcomes. This article provides an overview of lung cancer, explores CUR nanoparticles as a treatment approach, discusses the benefits and challenges of nanoparticle-based drug delivery, and highlights prospects for CUR nanoparticles in lung cancer treatment. Future research aims to optimize these delivery systems for improved efficacy and patient prognosis in lung cancer.

Keywords: lung cancer, curcumin, nanomedicine, nanoparticle-based drug delivery

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775 A Protocol Study of Accessibility: Physician’s Perspective Regarding Disability and Continuum of Care

Authors: Sidra Jawed

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The accessibility constructs and the body privilege discourse has been a major problem while dealing with health inequities and inaccessibility. The inherent problem in this arbitrary view of disability is that disability would never be the productive way of living. For past thirty years, disability activists have been working to differentiate ‘impairment’ from ‘disability’ and probing for more understanding of limitation imposed by society, this notion is ultimately known as the Social Model of Disability. The vulnerable population as disability community remains marginalized and seen relentlessly fighting to highlight the importance of social factors. It does not only constitute physical architectural barriers and famous blue symbol of access to the healthcare but also invisible, intangible barriers as attitudes and behaviours. Conventionally the idea of ‘disability’ has been laden with prejudiced perception amalgamating with biased attitude. Equity in contemporary setup necessitates the restructuring of organizational structure. Apparently simple, the complex interplay of disability and contemporary healthcare set up often ends up at negotiating vital components of basic healthcare needs. The role of society is indispensable when it comes to people with disability (PWD), everything from the access to healthcare to timely interventions are strongly related to the set up in place and the attitude of healthcare providers. It is vital to understand the association between assumptions and the quality of healthcare PWD receives in our global healthcare setup. Most of time the crucial physician-patient relationship with PWD is governed by the negative assumptions of the physicians. The multifaceted, troubled patient-physicians’ relationship has been neglected in past. To compound it, insufficient work has been done to explore physicians’ perspective about the disability and access to healthcare PWD have currently. This research project is directed towards physicians’ perspective on the intersection of health and access of healthcare for PWD. The principal aim of the study is to explore the perception of disability in family medicine physicians, highlighting the underpinning of medical perspective in healthcare institution. In the quest of removing barriers, the first step must be to identify the barriers and formulate a plan for future policies, involving all the stakeholders. There would be semi-structured interviews to explore themes as accessibility, medical training, construct of social model and medical model of disability, time limitations, financial constraints. The main research interest is to identify the obstacles to inclusion and marginalization continuing from the basic living necessities to wide health inequity in present society. Physicians point of view is largely missing from the research landscape and the current forum of knowledge with regards to physicians’ standpoint. This research will provide policy makers with a starting point and comprehensive background knowledge that can be a stepping stone for future researches and furthering the knowledge translation process to strengthen healthcare. Additionally, it would facilitate the process of knowledge translation between the much needed medical and disability community.

Keywords: disability, physicians, social model, accessibility

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774 Selective Extraction of Lithium from Native Geothermal Brines Using Lithium-ion Sieves

Authors: Misagh Ghobadi, Rich Crane, Karen Hudson-Edwards, Clemens Vinzenz Ullmann

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Lithium is recognized as the critical energy metal of the 21st century, comparable in importance to coal in the 19th century and oil in the 20th century, often termed 'white gold'. Current global demand for lithium, estimated at 0.95-0.98 million metric tons (Mt) of lithium carbonate equivalent (LCE) annually in 2024, is projected to rise to 1.87 Mt by 2027 and 3.06 Mt by 2030. Despite anticipated short-term stability in supply and demand, meeting the forecasted 2030 demand will require the lithium industry to develop an additional capacity of 1.42 Mt of LCE annually, exceeding current planned and ongoing efforts. Brine resources constitute nearly 65% of global lithium reserves, underscoring the importance of exploring lithium recovery from underutilized sources, especially geothermal brines. However, conventional lithium extraction from brine deposits faces challenges due to its time-intensive process, low efficiency (30-50% lithium recovery), unsuitability for low lithium concentrations (<300 mg/l), and notable environmental impacts. Addressing these challenges, direct lithium extraction (DLE) methods have emerged as promising technologies capable of economically extracting lithium even from low-concentration brines (>50 mg/l) with high recovery rates (75-98%). However, most studies (70%) have predominantly focused on synthetic brines instead of native (natural/real), with limited application of these approaches in real-world case studies or industrial settings. This study aims to bridge this gap by investigating a geothermal brine sample collected from a real case study site in the UK. A Mn-based lithium-ion sieve (LIS) adsorbent was synthesized and employed to selectively extract lithium from the sample brine. Adsorbents with a Li:Mn molar ratio of 1:1 demonstrated superior lithium selectivity and adsorption capacity. Furthermore, the pristine Mn-based adsorbent was modified through transition metals doping, resulting in enhanced lithium selectivity and adsorption capacity. The modified adsorbent exhibited a higher separation factor for lithium over major co-existing cations such as Ca, Mg, Na, and K, with separation factors exceeding 200. The adsorption behaviour was well-described by the Langmuir model, indicating monolayer adsorption, and the kinetics followed a pseudo-second-order mechanism, suggesting chemisorption at the solid surface. Thermodynamically, negative ΔG° values and positive ΔH° and ΔS° values were observed, indicating the spontaneity and endothermic nature of the adsorption process.

Keywords: adsorption, critical minerals, DLE, geothermal brines, geochemistry, lithium, lithium-ion sieves

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773 A Study of the Prevalence of Trichinellosis in Domestic and Wild Animals for the Region of Sofia, Bulgaria

Authors: Valeria Dilcheva, Svetlozara Petkova, Ivelin Vladov

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Nemathodes of the genus Trichinella are zoonotic parasites with a cosmopolitan distribution. More than 100 species of mammals, birds and reptiles are involved in the natural cycle of this nematode. At present, T. spiralis, T. pseudospiralis, and T. britovi have been found in Bulgaria. The existence of natural wildlife and domestic reservoirs of Trichinella spp. can be a serious threat to human health. Three trichinella isolates caused human trichinella infection outbreaks from three regions of Sofia City Province were used for the research: sample No. 1 - Ratus norvegicus, sample No. 2 – domestic pig (Sus scrofa domestica), sample No. 3 - domestic pig (Sus scrofa domestica). Trichinella larvae of the studied species were isolated via digestive method (pepsin, hydrochloric acid, water) at 37ºC by standard procedure and were determined by gender (male and female) based on their morphological characteristics. As a reference trichinella species were used: T. spiralis, T. pseudospiralis, T. nativa and T. britovi. Single male and female larvae of the three isolates were crossed with single male and female larvae of the reference trichinella species as well as reciprocally. As a result of cross-breeding, offspring of muscular larvae with T. spiralis and T. britovi were obtained, while in experiments with T. pseudospiralis and T. nativa, trichinella larvae were not found in the laboratory mice. The results obtained in the control groups indicate that the trichinella larvae used from the isolates and the four trichinella species are infective. Also, the infective ability of the F1 offspring from the successful cross-breeding between isolates and reference species was investigated. Through the data obtained in the experiment was found that isolates No. 1 and No. 2 belong to the species T. spiralis, and isolate No. 3 belongs to the species T. britovi. The results were confirmed by PCR and real-time PCR analysis. Thus the presence and circulation of the species T. spiralis and T. britovi in Bulgaria was confirmed. Probably the rodents (rats) are involved in the distribution of T. spiralis in urban environment. The species T. britovi found in a domestic pig speaks of some contact with wild animals for which T. britovi is characteristic. The probable reason is that a large number of farmers in Bulgaria practice the free-range breeding of domestic pigs. Part of the farmers also used as food for domestic pigs waste products from the game (foxes, jackals, bears, wolves) and probably thus the infection was obtained. The distribution range of trichinella species in Bulgaria is not strictly outlined. It is believed that T. spiralis is most common in domestic animals and T. britovi and T. pseudospiralis are characteristic of wildlife. To answer the question whether wild and synanthropic animals are infected with the same or different trichinella species, which species predominate in nature and what their distribution among different hosts is, further research is required.

Keywords: cross-breeding, Sofia, trichinellosis, Trichinella britovi, Trichinella spiralis

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772 Statistical Analysis to Compare between Smart City and Traditional Housing

Authors: Taha Anjamrooz, Sareh Rajabi, Ayman Alzaatreh

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Smart cities are playing important roles in real life. Integration and automation between different features of modern cities and information technologies improve smart city efficiency, energy management, human and equipment resource management, life quality and better utilization of resources for the customers. One of difficulties in this path, is use, interface and link between software, hardware, and other IT technologies to develop and optimize processes in various business fields such as construction, supply chain management and transportation in parallel to cost-effective and resource reduction impacts. Also, Smart cities are certainly intended to demonstrate a vital role in offering a sustainable and efficient model for smart houses while mitigating environmental and ecological matters. Energy management is one of the most important matters within smart houses in the smart cities and communities, because of the sensitivity of energy systems, reduction in energy wastage and maximization in utilizing the required energy. Specially, the consumption of energy in the smart houses is important and considerable in the economic balance and energy management in smart city as it causes significant increment in energy-saving and energy-wastage reduction. This research paper develops features and concept of smart city in term of overall efficiency through various effective variables. The selected variables and observations are analyzed through data analysis processes to demonstrate the efficiency of smart city and compare the effectiveness of each variable. There are ten chosen variables in this study to improve overall efficiency of smart city through increasing effectiveness of smart houses using an automated solar photovoltaic system, RFID System, smart meter and other major elements by interfacing between software and hardware devices as well as IT technologies. Secondly to enhance aspect of energy management by energy-saving within smart house through efficient variables. The main objective of smart city and smart houses is to reproduce energy and increase its efficiency through selected variables with a comfortable and harmless atmosphere for the customers within a smart city in combination of control over the energy consumption in smart house using developed IT technologies. Initially the comparison between traditional housing and smart city samples is conducted to indicate more efficient system. Moreover, the main variables involved in measuring overall efficiency of system are analyzed through various processes to identify and prioritize the variables in accordance to their influence over the model. The result analysis of this model can be used as comparison and benchmarking with traditional life style to demonstrate the privileges of smart cities. Furthermore, due to expensive and expected shortage of natural resources in near future, insufficient and developed research study in the region, and available potential due to climate and governmental vision, the result and analysis of this study can be used as key indicator to select most effective variables or devices during construction phase and design

Keywords: smart city, traditional housing, RFID, photovoltaic system, energy efficiency, energy saving

Procedia PDF Downloads 108
771 An in silico Approach for Exploring the Intercellular Communication in Cancer Cells

Authors: M. Cardenas-Garcia, P. P. Gonzalez-Perez

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Intercellular communication is a necessary condition for cellular functions and it allows a group of cells to survive as a population. Throughout this interaction, the cells work in a coordinated and collaborative way which facilitates their survival. In the case of cancerous cells, these take advantage of intercellular communication to preserve their malignancy, since through these physical unions they can send signs of malignancy. The Wnt/β-catenin signaling pathway plays an important role in the formation of intercellular communications, being also involved in a large number of cellular processes such as proliferation, differentiation, adhesion, cell survival, and cell death. The modeling and simulation of cellular signaling systems have found valuable support in a wide range of modeling approaches, which cover a wide spectrum ranging from mathematical models; e.g., ordinary differential equations, statistical methods, and numerical methods– to computational models; e.g., process algebra for modeling behavior and variation in molecular systems. Based on these models, different simulation tools have been developed from mathematical ones to computational ones. Regarding cellular and molecular processes in cancer, its study has also found a valuable support in different simulation tools that, covering a spectrum as mentioned above, have allowed the in silico experimentation of this phenomenon at the cellular and molecular level. In this work, we simulate and explore the complex interaction patterns of intercellular communication in cancer cells using the Cellulat bioinformatics tool, a computational simulation tool developed by us and motivated by two key elements: 1) a biochemically inspired model of self-organizing coordination in tuple spaces, and 2) the Gillespie’s algorithm, a stochastic simulation algorithm typically used to mimic systems of chemical/biochemical reactions in an efficient and accurate way. The main idea behind the Cellulat simulation tool is to provide an in silico experimentation environment that complements and guides in vitro experimentation in intra and intercellular signaling networks. Unlike most of the cell signaling simulation tools, such as E-Cell, BetaWB and Cell Illustrator which provides abstractions to model only intracellular behavior, Cellulat is appropriate for modeling both intracellular signaling and intercellular communication, providing the abstractions required to model –and as a result, simulate– the interaction mechanisms that involve two or more cells, that is essential in the scenario discussed in this work. During the development of this work we made evident the application of our computational simulation tool (Cellulat) for the modeling and simulation of intercellular communication between normal and cancerous cells, and in this way, propose key molecules that may prevent the arrival of malignant signals to the cells that surround the tumor cells. In this manner, we could identify the significant role that has the Wnt/β-catenin signaling pathway in cellular communication, and therefore, in the dissemination of cancer cells. We verified, using in silico experiments, how the inhibition of this signaling pathway prevents that the cells that surround a cancerous cell are transformed.

Keywords: cancer cells, in silico approach, intercellular communication, key molecules, modeling and simulation

Procedia PDF Downloads 247
770 Collaborative Program Student Community Service as a New Approach for Development in Rural Area in Case of Western Java

Authors: Brian Yulianto, Syachrial, Saeful Aziz, Anggita Clara Shinta

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Indonesia, with a population of about two hundred and fifty million people in quantity, indicates the outstanding wealth of human resources. Hundreds of millions of the population scattered in various communities in various regions in Indonesia with the different characteristics of economic, social and unique culture. Broadly speaking, the community in Indonesia is divided into two classes, namely urban communities and rural communities. The rural communities characterized by low potential and management of natural and human resources, limited access of development, and lack of social and economic infrastructure, and scattered and isolated population. West Java is one of the provinces with the largest population in Indonesia. Based on data from the Central Bureau of Statistics in 2015 the number of population in West Java reached 46.7096 million souls spread over 18 districts and 9 cities. The big difference in geographical and social conditions of people in West Java from one region to another, especially the south to the north causing the gap is high. It is closely related to the flow of investment to promote the area. Poverty and underdevelopment are the classic problems that occur on a massive scale in the region as the effects of inequity in development. South Cianjur and Tasikmalaya area South became one of the portraits area where the existing potential has not been capable of prospering society. Tri Dharma College not only define the College as a pioneer implementation of education and research to improve the quality of human resources but also demanded to be a pioneer in the development through the concept of public service. Bandung Institute of Technology as one of the institutions of higher education to implement community service system through collaborative community work program "one of the university community" as one approach to developing villages. The program is based Community Service, where students are not only required to be able to take part in community service, but also able to develop a community development strategy that is comprehensive and integrity in cooperation with government agencies and non-government related as a real form of effort alignment potential, position and role from various parties. Areas of western Java in particular have high poverty rates and disparity. On the other hand, there are three fundamental pillars in the development of rural communities, namely economic development, community development, and the integrated infrastructure development. These pillars require the commitment of all components of community, including the students and colleges for upholding success. College’s community program is one of the approaches in the development of rural communities. ITB is committed to implement as one form of student community service as community-college programs that integrate all elements of the community which is called Kuliah Kerja Nyata-Thematic.

Keywords: development in rural area, collaborative, student community service, Kuliah Kerja Nyata-Thematic ITB

Procedia PDF Downloads 218
769 Antimicrobial and Aroma Finishing of Organic Cotton Knits Using Vetiver Oil Microcapsules for Health Care Textiles

Authors: K. J. Sannapapamma, H. Malligawad Lokanath, Sakeena Naikwadi

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Eco-friendly textiles are gaining importance among the consumers and textile manufacturers in the healthcare sector due to increased environmental pollution which leads to several health and environmental hazards. Hence, the research was designed to cultivate and develop the organic cotton knit, to prepare and characterize the Vetiver oil microcapsules for textile finishing and to access the wash durability of finished knits. The cotton SAHANA variety grown under organic production systems was processed and spun into 30 single yarn dyed with four natural colorants (Arecanut slurry, Eucalyptus leaves, Pomegranate rind and Indigo) and eco dyed yarn was further used for development of single jersy knitted fabric. Vetiveria zizanioides is an aromatic grass which is being traditionally used in medicine and perfumery. Vetiver essential oil was used for preparation of microcapsules by interfacial polymerization technique subjected to Gas Chromatography Mass Spectrometry (GCMS), Fourier Transform Infrared Spectroscopy (FTIR), Thermo Gravimetric Analyzer (TGA) and Scanning Electron Microscope (SEM) for characterization of microcapsules. The knitted fabric was finished with vetiver oil microcapsules by exhaust and pad dry cure methods. The finished organic knit was assessed for laundering on antimicrobial efficiency and aroma intensity. GCMS spectral analysis showed that, diethyl phthalate (28%) was the major compound found in vetiver oil followed by isoaromadendrene epoxide (7.72%), beta-vetivenene (6.92%), solavetivone (5.58%), aromadenderene, azulene and khusimol. Bioassay explained that, the vetiver oil and diluted vetiver oil possessed greater zone of inhibition against S. aureus and E. coli than the coconut oil. FTRI spectra of vetiver oil and microcapsules possessed similar peaks viz., C-H, C=C & C꞊O stretching and additionally oil microcapsules possessed the peak of 3331.24 cm-1 at 91.14 transmittance was attributed to N-H stretches. TGA of oil microcapsules revealed that, there was a minimum weight loss (5.835%) recorded at 467.09°C compared to vetiver oil i.e., -3.026% at the temperature of 396.24°C. The shape of the microcapsules was regular and round, some were spherical in shape and few were rounded by small aggregates. Irrespective of methods of application, organic cotton knits finished with microcapsules by pad dry cure method showed maximum zone of inhibition compared to knits finished by exhaust method against S. aureus and E. coli. The antimicrobial activity of the finished samples was subjected to multiple washing which indicated that knits finished with pad dry cure method showed a zone of inhibition even after 20th wash and better aroma retention compared to knits finished with the exhaust method of application. Further, the group of respondents rated that the 5th washed samples had the greater aroma intensity in both the methods than the other samples. Thus, the vetiver microencapsulated organic cotton knits are free from hazardous chemicals and have multi-functional properties that can be suitable for medical and healthcare textiles.

Keywords: exhaust and pad dry cure finishing, interfacial polymerization, organic cotton knits, vetiver oil microcapsules

Procedia PDF Downloads 276
768 The Home as Memory Palace: Three Case Studies of Artistic Representations of the Relationship between Individual and Collective Memory and the Home

Authors: Laura M. F. Bertens

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The houses we inhabit are important containers of memory. As homes, they take on meaning for those who live inside, and memories of family life become intimately tied up with rooms, windows, and gardens. Each new family creates a new layer of meaning, resulting in a palimpsest of family memory. These houses function quite literally as memory palaces, as a walk through a childhood home will show; each room conjures up images of past events. Over time, these personal memories become woven together with the cultural memory of countries and generations. The importance of the home is a central theme in art, and several contemporary artists have a special interest in the relationship between memory and the home. This paper analyses three case studies in order to get a deeper understanding of the ways in which the home functions and feels like a memory palace, both on an individual and on a collective, cultural level. Close reading of the artworks is performed on the theoretical intersection between Art History and Cultural Memory Studies. The first case study concerns works from the exhibition Mnemosyne by the artist duo Anne and Patrick Poirier. These works combine interests in architecture, archaeology, and psychology. Models of cities and fantastical architectural designs resemble physical structures (such as the brain), architectural metaphors used in representing the concept of memory (such as the memory palace), and archaeological remains, essential to our shared cultural memories. Secondly, works by Do Ho Suh will help us understand the relationship between the home and memory on a far more personal level; outlines of rooms from his former homes, made of colourful, transparent fabric and combined into new structures, provide an insight into the way these spaces retain individual memories. The spaces have been emptied out, and only the husks remain. Although the remnants of walls, light switches, doors, electricity outlets, etc. are standard, mass-produced elements found in many homes and devoid of inherent meaning, together they remind us of the emotional significance attached to the muscle memory of spaces we once inhabited. The third case study concerns an exhibition in a house put up for sale on the Dutch real estate website Funda. The house was built in 1933 by a Jewish family fleeing from Germany, and the father and son were later deported and killed. The artists Anne van As and CA Wertheim have used the history and memories of the house as a starting point for an exhibition called (T)huis, a combination of the Dutch words for home and house. This case study illustrates the way houses become containers of memories; each new family ‘resets’ the meaning of a house, but traces of earlier memories remain. The exhibition allows us to explore the transition of individual memories into shared cultural memory, in this case of WWII. Taken together, the analyses provide a deeper understanding of different facets of the relationship between the home and memory, both individual and collective, and the ways in which art can represent these.

Keywords: Anne and Patrick Poirier, cultural memory, Do Ho Suh, home, memory palace

Procedia PDF Downloads 155
767 Phytochemical and Vitamin Composition of Wild Edible Plants Consumed in South West Ethiopia

Authors: Abebe Yimer, Sirawdink Fikereyesus Forsido, Getachew Addis, Abebe Ayelign

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Background: Oxidative stress has been an important health problem as itinduceschronic diseases such as cancer, cardiovascular, diabetics, and neurodegenerative disease. Plant source natural antioxidant has gained attention as synthetic antioxidant negatively impact human health. Wild edible plants arecheap source of dietary-medicine in mainly rural communityin south-west Ethiopia and elsewhere the country. Thus, the study aimed to determine total pheneol,flavoinoids, antioxidant, vitamin C, and beta-carotene content from wild edible plants Solanum nigrum L., Vigna membranacea A. Rich, Dioscorea praehensilis Benth., Trilepisium madagascariense D.C.andCleome gynandra L. Methods: Methanol was used to extract samples of oven-dried edible plants. Total phenolic compound (TPC) was determined using a Folin Ciocalteu method, whereas total flavonoid content (TFC) was determined using the Aluminium chloride colorimetric method. By using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) tests, antioxidant activities were evaluated in vitro. Additionally, beta-carotene was assessed using a spectrophotometric technique, whilst vitamin C was determined using a titration approach. Results: Total flavonoid contentranged from 0.85±0.03 to 11.25±0.01 mg CE/g in D. praehensilis Benth. tuber and C. gynandra L, respectively. Total phenolic compounds varied from 0.25±0.06 GAE/g in D. praehensilis Benth tuber to 35.73±2.52 GAE/g in S.nigrum L. leaves. In the DPPH test, the highest antioxidant value (87.65%) was obtained in the S.nigrum L. leaves, whereas the smallest amount of antioxidant (50.12%)was contained in D. praehensilis Benth tuber. Similarly in FRAP assay,D. praehensilis Benth tuber showed the least reducing potential(49.16± 2.13mM Fe2+/100 g)whilst the highest reducing potential was presented in the S.nigrum L. leaves(188.12±1.13 mM Fe2+/100 g). The beta-carotene content was found between 11.81±0.00 mg/100g in D. praehensilis Benth tubers to 34.49±0.95 mg/100g in V. membranacea A. Rich leaves. The concentration of vitamin C ranged from 10.00±0.61 in D. praehensilis Benth tubers to 45±1.80 mg/100g in V. membranacea A. Rich leaves. The results showed that high positive linear correlations between TPC and TFC of WEPs (r=0.828), as well as between FRAP and total phenolic contents (r = 0.943) and FRAP and vitamin C (r= 0.928). Conclusion: These findings showed the total phenolic and flavonoid contents of Solanum nigrum L. and Cleome gynandra L, respectively, are abundant. The outcome may be used as a natural supply of dietary antioxidants, which may be useful in preventing oxidative stress. The study's findings also showed that Vigna membranacea A. Rich leaves were cheap source of vitamin C and beta-carotene for people who consumed these wild green. Additional research on the in vivo antioxidant activity, toxicological analysis, and promotion of these wild food plants for agricultural production should be taken into consideration.

Keywords: antioxidant activity, beta-carotene, flavonoids, phenolic content, and vitamin c

Procedia PDF Downloads 98
766 Methodology for the Determination of Triterpenic Compounds in Apple Extracts

Authors: Mindaugas Liaudanskas, Darius Kviklys, Kristina Zymonė, Raimondas Raudonis, Jonas Viškelis, Norbertas Uselis, Pranas Viškelis, Valdimaras Janulis

Abstract:

Apples are among the most commonly consumed fruits in the world. Based on data from the year 2014, approximately 84.63 million tons of apples are grown per annum. Apples are widely used in food industry to produce various products and drinks (juice, wine, and cider); they are also used unprocessed. Apples in human diet are an important source of different groups of biological active compounds that can positively contribute to the prevention of various diseases. They are a source of various biologically active substances – especially vitamins, organic acids, micro- and macro-elements, pectins, and phenolic, triterpenic, and other compounds. Triterpenic compounds, which are characterized by versatile biological activity, are the biologically active compounds found in apples that are among the most promising and most significant for human health. A specific analytical procedure including sample preparation and High Performance Liquid Chromatography (HPLC) analysis was developed, optimized, and validated for the detection of triterpenic compounds in the samples of different apples, their peels, and flesh from widespread apple cultivars 'Aldas', 'Auksis', 'Connel Red', 'Ligol', 'Lodel', and 'Rajka' grown in Lithuanian climatic conditions. The conditions for triterpenic compound extraction were optimized: the solvent of the extraction was 100% (v/v) acetone, and the extraction was performed in an ultrasound bath for 10 min. Isocratic elution (the eluents ratio being 88% (solvent A) and 12% (solvent B)) for a rapid separation of triterpenic compounds was performed. The validation of the methodology was performed on the basis of the ICH recommendations. The following characteristics of validation were evaluated: the selectivity of the method (specificity), precision, the detection and quantitation limits of the analytes, and linearity. The obtained parameters values confirm suitability of methodology to perform analysis of triterpenic compounds. Using the optimised and validated HPLC technique, four triterpenic compounds were separated and identified, and their specificity was confirmed. These compounds were corosolic acid, betulinic acid, oleanolic acid, and ursolic acid. Ursolic acid was the dominant compound in all the tested apple samples. The detected amount of betulinic acid was the lowest of all the identified triterpenic compounds. The greatest amounts of triterpenic compounds were detected in whole apple and apple peel samples of the 'Lodel' cultivar, and thus apples and apple extracts of this cultivar are potentially valuable for use in medical practice, for the prevention of various diseases, for adjunct therapy, for the isolation of individual compounds with a specific biological effect, and for the development and production of dietary supplements and functional food enriched in biologically active compounds. Acknowledgements. This work was supported by a grant from the Research Council of Lithuania, project No. MIP-17-8.

Keywords: apples, HPLC, triterpenic compounds, validation

Procedia PDF Downloads 168
765 An Evolutionary Approach for Automated Optimization and Design of Vivaldi Antennas

Authors: Sahithi Yarlagadda

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The design of antenna is constrained by mathematical and geometrical parameters. Though there are diverse antenna structures with wide range of feeds yet, there are many geometries to be tried, which cannot be customized into predefined computational methods. The antenna design and optimization qualify to apply evolutionary algorithmic approach since the antenna parameters weights dependent on geometric characteristics directly. The evolutionary algorithm can be explained simply for a given quality function to be maximized. We can randomly create a set of candidate solutions, elements of the function's domain, and apply the quality function as an abstract fitness measure. Based on this fitness, some of the better candidates are chosen to seed the next generation by applying recombination and permutation to them. In conventional approach, the quality function is unaltered for any iteration. But the antenna parameters and geometries are wide to fit into single function. So, the weight coefficients are obtained for all possible antenna electrical parameters and geometries; the variation is learnt by mining the data obtained for an optimized algorithm. The weight and covariant coefficients of corresponding parameters are logged for learning and future use as datasets. This paper drafts an approach to obtain the requirements to study and methodize the evolutionary approach to automated antenna design for our past work on Vivaldi antenna as test candidate. The antenna parameters like gain, directivity, etc. are directly caged by geometries, materials, and dimensions. The design equations are to be noted here and valuated for all possible conditions to get maxima and minima for given frequency band. The boundary conditions are thus obtained prior to implementation, easing the optimization. The implementation mainly aimed to study the practical computational, processing, and design complexities that incur while simulations. HFSS is chosen for simulations and results. MATLAB is used to generate the computations, combinations, and data logging. MATLAB is also used to apply machine learning algorithms and plotting the data to design the algorithm. The number of combinations is to be tested manually, so HFSS API is used to call HFSS functions from MATLAB itself. MATLAB parallel processing tool box is used to run multiple simulations in parallel. The aim is to develop an add-in to antenna design software like HFSS, CSTor, a standalone application to optimize pre-identified common parameters of wide range of antennas available. In this paper, we have used MATLAB to calculate Vivaldi antenna parameters like slot line characteristic impedance, impedance of stripline, slot line width, flare aperture size, dielectric and K means, and Hamming window are applied to obtain the best test parameters. HFSS API is used to calculate the radiation, bandwidth, directivity, and efficiency, and data is logged for applying the Evolutionary genetic algorithm in MATLAB. The paper demonstrates the computational weights and Machine Learning approach for automated antenna optimizing for Vivaldi antenna.

Keywords: machine learning, Vivaldi, evolutionary algorithm, genetic algorithm

Procedia PDF Downloads 104
764 Development and Obtaining of Solid Dispersions to Increase the Solubility of Efavirenz in Anti-HIV Therapy

Authors: Salvana P. M. Costa, Tarcyla A. Gomes, Giovanna C. R. M. Schver, Leslie R. M. Ferraz, Cristovão R. Silva, Magaly A. M. Lyra, Danilo A. F. Fonte, Larissa A. Rolim, Amanda C. Q. M. Vieira, Miracy M. Albuquerque, Pedro J. Rolim-neto

Abstract:

Efavirenz (EFV) is considered one of the most widely used anti-HIV drugs. However, it is classified as a drug class II (poorly soluble, highly permeable) according to the biopharmaceutical classification system, presenting problems of absorption in the gastrointestinal tract and thereby inadequate bioavailability for its therapeutic action. This study aimed to overcome these barriers by developing and obtaining solid dispersions (SD) in order to increase the EFZ bioavailability. For the development of SD with EFV, theoretical and practical studies were initially performed. Thus, there was a choice of a carrier to be used. For this, it was analyzed the various criteria such as glass transition temperature of the polymer, intra- and intermolecular interactions of hydrogen bonds between drug and polymer, the miscibility between the polymer and EFV. The choice of the obtainment method of the SD came from the analysis of which method is the most consolidated in both industry and literature. Subsequently, the choice of drug and carrier concentrations in the dispersions was carried out. In order to obtain DS to present the drug in its amorphous form, as the DS were obtained, they were analyzed by X-ray diffraction (XRD). SD are more stable the higher the amount of polymer present in the formulation. With this assumption, a SD containing 10% of drug was initially prepared and then this proportion was increased until the XRD showed the presence of EFV in its crystalline form. From this point, it was not produced SD with a higher concentration of drug. Thus, it was allowed to select PVP-K30, PVPVA 64 and the SOLUPLUS formulation as carriers, once it was possible the formation of hydrogen bond between EFV and polymers since these have hydrogen acceptor groups capable of interacting with the donor group of the drug hydrogen. It is worth mentioning also that the films obtained, independent of concentration used, were presented homogeneous and transparent. Thus, it can be said that the EFV is miscible in the three polymers used in the study. The SD and Physical Mixtures (PM) with these polymers were prepared by the solvent method. The EFV diffraction profile showed main peaks at around 2θ of 6,24°, in addition to other minor peaks at 14,34°, 17,08°, 20,3°, 21,36° and 25,06°, evidencing its crystalline character. Furthermore, the polymers showed amorphous nature, as evidenced by the absence of peaks in their XRD patterns. The XRD patterns showed the PM overlapping profile of the drug with the polymer, indicating the presence of EFV in its crystalline form. Regardless the proportion of drug used in SD, all the samples showed the same characteristics with no diffraction peaks EFV, demonstrating the behavior amorphous products. Thus, the polymers enabled, effectively, the formation of amorphous SD, probably due to the potential hydrogen bonds between them and the drug. Moreover, the XRD analysis showed that the polymers were able to maintain its amorphous form in a concentration of up to 80% drug.

Keywords: amorphous form, Efavirenz, solid dispersions, solubility

Procedia PDF Downloads 564
763 Family Cohesion, Social Networks, and Cultural Differences in Latino and Asian American Help Seeking Behaviors

Authors: Eileen Y. Wong, Katherine Jin, Anat Talmon

Abstract:

Background: Help seeking behaviors are highly contingent on socio-cultural factors such as ethnicity. Both Latino and Asian Americans underutilize mental health services compared to their White American counterparts. This difference may be related to the composite of one’s social support system, which includes family cohesion and social networks. Previous studies have found that Latino families are characterized by higher levels of family cohesion and social support, and Asian American families with greater family cohesion exhibit lower levels of help seeking behaviors. While both are broadly considered collectivist communities, within-culture variability is also significant. Therefore, this study aims to investigate the relationship between help seeking behaviors in the two cultures with levels of family cohesion and strength of social network. We also consider such relationships in light of previous traumatic events and diagnoses, particularly post-traumatic stress disorder (PTSD), to understand whether clinically diagnosed individuals differ in their strength of network and help seeking behaviors. Method: An adult sample (N = 2,990) from the National Latino and Asian American Study (NLAAS) provided data on participants’ social network, family cohesion, likelihood of seeking professional help, and DSM-IV diagnoses. T-tests compared Latino American (n = 1,576) and Asian American respondents (n = 1,414) in strength of social network, level of family cohesion, and likelihood of seeking professional help. Linear regression models were used to identify the probability of help-seeking behavior based on ethnicity, PTSD diagnosis, and strength of social network. Results: Help-seeking behavior was significantly associated with family cohesion and strength of social network. It was found that higher frequency of expressing one’s feelings with family significantly predicted lower levels of help-seeking behaviors (β = [-.072], p = .017), while higher frequency of spending free time with family significantly predicted higher levels of help-seeking behaviors (β = [.129], p = .002) in the Asian American sample. Subjective importance of family relations compared to that of one’s peers also significantly predict higher levels of help-seeking behaviors (β = [.095], p = .011) in the Asian American sample. Frequency of sharing one’s problems with relatives significantly predicted higher levels of help-seeking behaviors (β = [.113], p < .01) in the Latino American sample. A PTSD diagnosis did not have any significant moderating effect. Conclusion: Considering the underutilization of mental health services in Latino and Asian American minority groups, it is crucial to understand ways in which help seeking behavior can be encouraged. Our findings suggest that different dimensions within family cohesion and social networks have differential impacts on help-seeking behavior. Given the multifaceted nature of family cohesion and cultural relevance, the implications of our findings for theory and practice will be discussed.

Keywords: family cohesion, social networks, Asian American, Latino American, help-seeking behavior

Procedia PDF Downloads 62
762 Morphological Transformation of Traditional Cities: The Case Study of the Historic Center of the City of Najaf

Authors: Sabeeh Lafta Farhan, Ihsan Abbass Jasim, Sohaib Kareem Al-Mamoori

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This study addresses the subject of transformation of urban structures and how does this transformation affect the character of traditional cities, which represents the research issue. Hence, the research has aimed at studying and learning about the urban structure characteristics and morphological transformation features in the traditional cities centers, and to look for means and methods to preserve the character of those cities. Cities are not merely locations inhabited by a large number of people, they are political and legal entities, in addition to economic activities that distinguish these cities, thus, they are a complex set of institutions, and the transformation in urban environment cannot be recognized without understanding these relationships. The research presumes an existing impact of urbanization on the properties of traditional structure of the Holy City of Najaf. The research has defined urbanization as restructuring and re-planning of urban areas that have lost their functions and bringing them into social and cultural life in the city, to be able to serve economy in order to better respond to the needs of users. Sacred Cities provide the organic connection between acts of worship and dealings and reveal the mechanisms and reasons behind the regulatory nature of the sacred shrine and their role in achieving organizational assimilation of urban morphology. The research has reached a theoretical framework of the particulars of urbanization. This framework has been applied to the historic center of the old city of Najaf, where the most important findings of the research were that the visual and structural dominant presence of holy shrine of Imam Ali (peace be upon him) remains to emphasize the visual particularity, and the main role of the city, which hosts one of the most important Muslim shrines in the world, in addition to the visible golden dome rising above the skyline, and the Imam Ali Mosque the hub and the center for religious activities. Thus, in view of being a place of main importance and a symbol of religious and Islamic culture, it is very important to have the shrine of Imam Ali (AS) prevailing on all zones of re-development in the old city. Consequently, the research underlined that the distinctive and unique character of the city of Najaf did not proceed from nothing, but was achieved through the unrivaled characteristics and features possessed by the city of Najaf alone, which allowed it and enabled it to occupy this status among the Arab and Muslim cities. That is why the activities arising from the development have to enhance the historical role of the city in order to have this development as clear support, strength and further addition to the city assets and its cultural heritage, and not seeing the developmental activities crushing the city urban traditional fabric, cultural heritage and its historical specificity.

Keywords: Iraq, the city of Najaf, heritage, traditional cities, morphological transformation

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761 Improving Efficiency of Organizational Performance: The Role of Human Resources in Supply Chains and Job Rotation Practice

Authors: Moh'd Anwer Al-Shboul

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Jordan Customs (JC) has been established to achieve objectives that must be consistent with the guidance of the wise leadership and its aspirations toward tomorrow. Therefore, it has developed several needed tools to provide a distinguished service to simplify work procedures and used modern technologies. A supply chain (SC) consists of all parties that are involved directly or indirectly in order to fulfill a customer request, which includes manufacturers, suppliers, shippers, retailers and even customer brokers. Within each firm, the SC includes all functions involved in receiving a filling a customers’ requests; one of the main functions include customer service. JC and global SCs are evolving into dynamic environment, which requires flexibility, effective communication, and team management. Thus, human resources (HRs) insight in these areas are critical for the effective development of global process network. The importance of HRs has increased significantly due to the role of employees depends on their knowledge, competencies, abilities, skills, and motivations. Strategic planning in JC began at the end of the 1990’s including operational strategy for Human Resource Management and Development (HRM&D). However, a huge transformation in human resources happened at the end of 2006; new employees’ regulation for customs were prepared, approved and applied at the end of 2007. Therefore, many employees lost their positions, while others were selected based on professorial recruitment and selection process (enter new blood). One of several policies that were applied by human resources in JC department is job rotation. From the researcher’s point of view, it was not based on scientific basis to achieve its goals and objectives, which at the end leads to having a significant negative impact on the Organizational Performance (OP) and weak job rotation approach. The purpose of this study is to call attention to re-review the applying process and procedure of job rotation that HRM directorate is currently applied at JC. Furthermore, it presents an overview of managing the HRs in the SC network that affects their success. The research methodology employed in this study was described as qualitative by conducting few interviews with managers, internal employee, external clients and reviewing the related literature to collect some qualitative data from secondary sources. Thus, conducting frequently and unstructured job rotation policy (i.e. monthly) will have a significant negative impact on JC performance as a whole. The results of this study show that the main impacts will affect on three main elements in JC: (1) internal employees' performance; (2) external clients, who are dealing with customs services; and finally, JC performance as a whole. In order to implement a successful and perfect job rotation technique at JC in a scientific way and to achieve its goals and objectives; JCs should be taken into consideration the proposed solutions and recommendations that will be presented in this study.

Keywords: efficiency, supply chain, human resources, job rotation, organizational performance, Jordan customs

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760 Closing the Loop between Building Sustainability and Stakeholder Engagement: Case Study of an Australian University

Authors: Karishma Kashyap, Subha D. Parida

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Rapid population growth and urbanization is creating pressure throughout the world. This has a dramatic effect on a lot of elements which include water, food, transportation, energy, infrastructure etc. as few of the key services. Built environment sector is growing concurrently to meet the needs of urbanization. Due to such large scale development of buildings, there is a need for them to be monitored and managed efficiently. Along with appropriate management, climate adaptation is highly crucial as well because buildings are one of the major sources of greenhouse gas emission in their operation phase. Buildings to be adaptive need to provide a triple bottom approach to sustainability i.e., being socially, environmentally and economically sustainable. Hence, in order to deliver these sustainability outcomes, there is a growing understanding and thrive towards switching to green buildings or renovating new ones as per green standards wherever possible. Academic institutions in particular have been following this trend globally. This is highly significant as universities usually have high occupancy rates because they manage a large building portfolio. Also, as universities accommodate the future generation of architects, policy makers etc., they have the potential of setting themselves as a best industry practice model for research and innovation for the rest to follow. Hence their climate adaptation, sustainable growth and performance management becomes highly crucial in order to provide the best services to users. With the objective of evaluating appropriate management mechanisms within academic institutions, a feasibility study was carried out in a recent 5-Star Green Star rated university building (housing the School of Construction) in Victoria (south-eastern state of Australia). The key aim was to understand the behavioral and social aspect of the building users, management and the impact of their relationship on overall building sustainability. A survey was used to understand the building occupant’s response and reactions in terms of their work environment and management. A report was generated based on the survey results complemented with utility and performance data which were then used to evaluate the management structure of the university. Followed by the report, interviews were scheduled with the facility and asset managers in order to understand the approach they use to manage the different buildings in their university campuses (old, new, refurbished), respective building and parameters incorporated in maintaining the Green Star performance. The results aimed at closing the communication and feedback loop within the respective institutions and assist the facility managers to deliver appropriate stakeholder engagement. For the wider design community, analysis of the data highlights the applicability and significance of prioritizing key stakeholders, integrating desired engagement policies within an institution’s management structures and frameworks and their effect on building performance

Keywords: building optimization, green building, post occupancy evaluation, stakeholder engagement

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759 The Effectiveness of Psychosocial Interventions for Survivors of Natural Disasters: A Systematic Review

Authors: Santhani M. Selveindran

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Background: Natural disasters are traumatic global events that are becoming increasing more common, with significant psychosocial impact on survivors. This impact results not only in psychosocial distress but, for many, can lead to psychosocial disorders and chronic psychopathology. While there are currently available interventions that seek to prevent and treat these psychosocial sequelae, their effectiveness is uncertain. The evidence-base is emerging with more primary studies evaluating the effectiveness of various psychosocial interventions for survivors of natural disasters, which remains to be synthesized. Aim of Review: To identify, critically appraise and synthesize the current evidence-base on the effectiveness of psychosocial interventions in preventing or treating Post-Traumatic Stress Disorder (PTSD), Major Depressive Disorder (MDD) and/or Generalized Anxiety Disorder (GAD) in adults and children who are survivors of natural disasters. Methods: A protocol was developed as a guide to carry out this review. A systematic search was conducted in eight international electronic databases, three grey literature databases, one dissertation and thesis repository, websites of six humanitarian and non-governmental organizations renowned for their work on natural disasters, as well as bibliographic and citation searching for eligible articles. Papers meeting the specific inclusion criteria underwent quality assessment using the Downs and Black checklist. Data were extracted from the included papers and analysed by way of narrative synthesis. Results: Database and website searching returned 3777 papers where 31 met the criteria for inclusion. Additional 2 papers were obtained through bibliographic and citation searching. Methodological quality of most papers was fair. Twenty-five studies evaluated psychological interventions, five, social interventions whereas three studies evaluated ‘mixed’ psychological and social interventions. All studies, irrespective of methodological quality, reported post-intervention reductions in symptom scores for PTSD, depression and/or anxiety and where assessed, reduced diagnosis of PTSD and MDD, and produced improvements in self-efficacy and quality of life. Statistically significant results were seen in 27 studies. However, three studies demonstrated that the evaluated interventions may not have been very beneficial. Conclusions: The overall positive results suggest that any psychosocial interventions are favourable and should be delivered to all natural disaster survivors, irrespective of age, country, and phase of disaster. Yet, heterogeneity and methodological shortcomings of the current evidence-base makes it difficult to draw definite conclusions needed to formulate categorical guidance or frameworks. Further, rigorously conducted research is needed in this area, although the feasibility of such, given the context and nature of the problem, is also recognized.

Keywords: psychosocial interventions, natural disasters, survivors, effectiveness

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758 Polymer Composites Containing Gold Nanoparticles for Biomedical Use

Authors: Bozena Tyliszczak, Anna Drabczyk, Sonia Kudlacik-Kramarczyk, Agnieszka Sobczak-Kupiec

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Introduction: Nanomaterials become one of the leading materials in the synthesis of various compounds. This is a reason for the fact that nano-size materials exhibit other properties compared to their macroscopic equivalents. Such a change in size is reflected in a change in optical, electric or mechanical properties. Among nanomaterials, particular attention is currently directed into gold nanoparticles. They find application in a wide range of areas including cosmetology or pharmacy. Additionally, nanogold may be a component of modern wound dressings, which antibacterial activity is beneficial in the viewpoint of the wound healing process. Specific properties of this type of nanomaterials result in the fact that they may also be applied in cancer treatment. Studies on the development of new techniques of the delivery of drugs are currently an important research subject of many scientists. This is due to the fact that along with the development of such fields of science as medicine or pharmacy, the need for better and more effective methods of administering drugs is constantly growing. The solution may be the use of drug carriers. These are materials that combine with the active substance and lead it directly to the desired place. A role of such a carrier may be played by gold nanoparticles that are able to covalently bond with many organic substances. This allows the combination of nanoparticles with active substances. Therefore gold nanoparticles are widely used in the preparation of nanocomposites that may be used for medical purposes with special emphasis on drug delivery. Methodology: As part of the presented research, synthesis of composites was carried out. The mentioned composites consisted of the polymer matrix and gold nanoparticles that were introduced into the polymer network. The synthesis was conducted with the use of a crosslinking agent, and photoinitiator and the materials were obtained by means of the photopolymerization process. Next, incubation studies were conducted using selected liquids that simulated fluids are occurring in the human body. The study allows determining the biocompatibility of the tested composites in relation to selected environments. Next, the chemical structure of the composites was characterized as well as their sorption properties. Conclusions: Conducted research allowed for the preliminary characterization of prepared polymer composites containing gold nanoparticles in the viewpoint of their application for biomedical use. Tested materials were characterized by biocompatibility in tested environments. What is more, synthesized composites exhibited relatively high swelling capacity that is essential in the viewpoint of their potential application as drug carriers. During such an application, composite swells and at the same time releases from its interior introduced active substance; therefore, it is important to check the swelling ability of such material. Acknowledgements: The authors would like to thank The National Science Centre (Grant no: UMO - 2016/21/D/ST8/01697) for providing financial support to this project. This paper is based upon work from COST Action (CA18113), supported by COST (European Cooperation in Science and Technology).

Keywords: nanocomposites, gold nanoparticles, drug carriers, swelling properties

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757 Integrated Manufacture of Polymer and Conductive Tracks for Functional Objects Fabrication

Authors: Barbara Urasinska-Wojcik, Neil Chilton, Peter Todd, Christopher Elsworthy, Gregory J. Gibbons

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The recent increase in the application of Additive Manufacturing (AM) of products has resulted in new demands on capability. The ability to integrate both form and function within printed objects is the next frontier in the 3D printing area. To move beyond prototyping into low volume production, we demonstrate a UK-designed and built AM hybrid system that combines polymer based structural deposition with digital deposition of electrically conductive elements. This hybrid manufacturing system is based on a multi-planar build approach to improve on many of the limitations associated with AM, such as poor surface finish, low geometric tolerance, and poor robustness. Specifically, the approach involves a multi-planar Material Extrusion (ME) process in which separated build stations with up to 5 axes of motion replace traditional horizontally-sliced layer modeling. The construction of multi-material architectures also involved using multiple print systems in order to combine both ME and digital deposition of conductive material. To demonstrate multi-material 3D printing, three thermoplastics, acrylonitrile butadiene styrene (ABS), polyamide 6,6/6 copolymers (CoPA) and polyamide 12 (PA) were used to print specimens, on top of which our high viscosity Ag-particulate ink was printed in a non-contact process, during which drop characteristics such as shape, velocity, and volume were assessed using a drop watching system. Spectroscopic analysis of these 3D printed materials in the IR region helped to determine the optimum in-situ curing system for implementation into the AM system to achieve improved adhesion and surface refinement. Thermal Analyses were performed to determine the printed materials glass transition temperature (Tg), stability and degradation behavior to find the optimum annealing conditions post printing. Electrical analysis of printed conductive tracks on polymer surfaces during mechanical testing (static tensile and 3-point bending and dynamic fatigue) was performed to assess the robustness of the electrical circuits. The tracks on CoPA, ABS, and PA exhibited low electrical resistance, and in case of PA resistance values of tracks remained unchanged across hundreds of repeated tensile cycles up to 0.5% strain amplitude. Our developed AM printer has the ability to fabricate fully functional objects in one build, including complex electronics. It enables product designers and manufacturers to produce functional saleable electronic products from a small format modular platform. It will make 3D printing better, faster and stronger.

Keywords: additive manufacturing, conductive tracks, hybrid 3D printer, integrated manufacture

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756 The Gypsy Community Facing the Sexual Orientation: An Empirical Approach to the Attitudes of the Gypsy Population of Granada Towards Homosexual Sex-Affective Relationships

Authors: Elena Arquer Cuenca

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The gypsy community has been a mistreated and rejected group since its arrival in the Iberian Peninsula in the 15th century. At present, despite being the largest ethnic minority group in Spain as well as in Europe, the different legal and social initiatives in favour of equality continue to suffer discrimination by the general society. This has fostered a strengthening of the endogroup accompanied by cultural conservatism as a form of self-protection. Despite the current trend of normalization of sexual diversity in modern societies, LGB people continue to suffer discrimination, especially in more traditional environments or communities. This rejection for reasons of sexual orientation within the family or community can hinder the free development of the person and compromise peaceful coexistence. The present work is intended as an approach to the attitudes of the gypsy population towards non-heterosexual sexual orientation. The objective is none other than ‘to know the appreciation that the gypsy population has about homosexual sex-affective relationships, in order to assess whether this has any impact on family and community coexistence’. The following specific objectives are derived from this general objective: ‘To find out whether there is a relationship between the dichotomous Roma gender system and the acceptance/rejection of homosexuality’; ‘to analyse whether sexual orientation has an impact on the coexistence of the Roman family and community’; ‘to analyse whether the historical discrimination suffered by the Roman population favours the maintenance of the patriarchal heterosexual reproductive family’; and lastly ‘to explore whether ICTs have promoted the process of normalisation and/or acceptance of homosexuality within the Roma community’. In order to achieve these objectives, a bibliographical and documentary review has been used, as well as the semi-structured interview technique, in which 4 gypsy people participated (2 women and 2 men of different ages). One of the main findings was the inappropriateness of the use of the homogenising category "Gypsy People" at present, given the great diversity among the Roma communities. Moreover, the difficulty in accepting homosexuality seems to be related to the fact that the heterosexual reproductive family has been the main survival mechanism of Roma communities over centuries. However, it will be concluded that attitudes towards homosexuality will vary depending on the socio-economic and cultural context and factors such as age or professed religion. Three main contributions of this research are: firstly, the inclusion of sexual orientation as a variable to be considered when analysing peaceful coexistence; secondly socio-historical dynamics and structures of inequality have been taken into account when analysing Roma attitudes towards homosexuality; and finally, the processual nature of socio-cultural changes has also been considered.

Keywords: gender, homosexuality, ICTs, peaceful coexistence, Roma community, sexual orientation

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755 Robust Inference with a Skew T Distribution

Authors: M. Qamarul Islam, Ergun Dogan, Mehmet Yazici

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There is a growing body of evidence that non-normal data is more prevalent in nature than the normal one. Examples can be quoted from, but not restricted to, the areas of Economics, Finance and Actuarial Science. The non-normality considered here is expressed in terms of fat-tailedness and asymmetry of the relevant distribution. In this study a skew t distribution that can be used to model a data that exhibit inherent non-normal behavior is considered. This distribution has tails fatter than a normal distribution and it also exhibits skewness. Although maximum likelihood estimates can be obtained by solving iteratively the likelihood equations that are non-linear in form, this can be problematic in terms of convergence and in many other respects as well. Therefore, it is preferred to use the method of modified maximum likelihood in which the likelihood estimates are derived by expressing the intractable non-linear likelihood equations in terms of standardized ordered variates and replacing the intractable terms by their linear approximations obtained from the first two terms of a Taylor series expansion about the quantiles of the distribution. These estimates, called modified maximum likelihood estimates, are obtained in closed form. Hence, they are easy to compute and to manipulate analytically. In fact the modified maximum likelihood estimates are equivalent to maximum likelihood estimates, asymptotically. Even in small samples the modified maximum likelihood estimates are found to be approximately the same as maximum likelihood estimates that are obtained iteratively. It is shown in this study that the modified maximum likelihood estimates are not only unbiased but substantially more efficient than the commonly used moment estimates or the least square estimates that are known to be biased and inefficient in such cases. Furthermore, in conventional regression analysis, it is assumed that the error terms are distributed normally and, hence, the well-known least square method is considered to be a suitable and preferred method for making the relevant statistical inferences. However, a number of empirical researches have shown that non-normal errors are more prevalent. Even transforming and/or filtering techniques may not produce normally distributed residuals. Here, a study is done for multiple linear regression models with random error having non-normal pattern. Through an extensive simulation it is shown that the modified maximum likelihood estimates of regression parameters are plausibly robust to the distributional assumptions and to various data anomalies as compared to the widely used least square estimates. Relevant tests of hypothesis are developed and are explored for desirable properties in terms of their size and power. The tests based upon modified maximum likelihood estimates are found to be substantially more powerful than the tests based upon least square estimates. Several examples are provided from the areas of Economics and Finance where such distributions are interpretable in terms of efficient market hypothesis with respect to asset pricing, portfolio selection, risk measurement and capital allocation, etc.

Keywords: least square estimates, linear regression, maximum likelihood estimates, modified maximum likelihood method, non-normality, robustness

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